(1) An electronic system that uses optical (light) pathways between chip modules rather than electricity.
(2) A chip that uses optical gates and pathways rather than electronic gates and pathways. This type of photonic processor provides considerably faster computations than today's electronic CPUs; however, the gate density is much larger, and a laser system must provide a light source. Nevertheless, the huge speed advantage makes up for the size disadvantage, and chips aimed at AI acceleration are emerging.
In the meantime, hybrid chips combining photonics and electronics are expected to become widely used before chips with all-optical gates and pathways are common. See
photonics.